Are cosmic rays influencing oceanic cloud coverage - or is it only El Nino?
Are cosmic rays influencing oceanic cloud coverage - or is it only El Nino?
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DOI：
10.1023/a:1005672825112
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发表时间：
2000-10-01
期刊：
影响因子：
4.8
通讯作者：
Farrar, PD
中科院分区：
文献类型：
--
作者：
Farrar, PD
国际卫星云气候学项目（ISCCP）提供的1986年7月至1991年6月期间的月平均（C2）云覆盖数据显示，与1986-1987年厄尔尼诺现象有关的全球和区域云覆盖变化很大。特别是太平洋，云覆盖率显示出强烈的区域差异。这与地球辐射收支实验测量的宽带短波红外云强迫的同期卫星观测结果一致。Svensmark和Friis-Christensen（1997年）指出，中低纬度海洋地区平均云覆盖率的时间序列曲线形状与宇宙射线通量强度的时间序列曲线形状相似。他们提出了一种因果关系-太阳周期对地球气候影响的“缺失环节”。本文对同一ISCCP C2资料的进一步时空分析表明，云覆盖变化模式是厄尔尼诺大气环流变化特征所预期的，削弱了宇宙射线作为气候强迫因子的可能性。
The monthly average (C2) cloud coverage data produced by the International Satellite Cloud Climatology Project (ISCCP) for the period of July 1986-June 1991 show strong global and regional cloud coverage variations associated with the El Nino of 1986-1987. The Pacific Ocean, in particular, shows strong regional variations in cloud coverage. These agree well with contemporaneous satellite observations of broadband shortwave infrared cloud forcing measured by the Earth Radiation Budget Experiment. Svensmark and Friis-Christensen (1997) noted a similarity between the shape of the time series curve of average cloud coverage fraction for mid- to low-latitude ocean-areas and the time series curve of cosmic ray flux intensity. They proposed a causal relationship - a 'missing link' for solar cycle influence on Earth climate. Further spatial and temporal analysis of the same ISCCP C2 data in this paper indicates that the cloud coverage variation patterns are those to be expected for the atmospheric circulation changes characteristic of El Nino, weakening the case for cosmic rays as a climatic forcing factor.